This disclosure is directed to an electrically powered automotive engine. The improved apparatus disclosed herein enhances that previous disclosure by provision of a pulse width modulator in the electric or power generating circuitry. The PWM controls the length of the pulse which is formed by it. The pulse length in part relates to or determines the total power applied to a given piston inasmuch as power is proportionate to the time integral of the pulse applied to the piston. If relatively long pulses are applied, proportionately more power is applied. The application of more power is an important factor, but it can only happen in controlled circumstances. It must be applied in a timely fashion, timely being defined as one dependent on the relative position of the piston. In other words, the power pulse that creates the magnetic field attracting the piston and thereby tending to move the piston must be timed so that the piston is not too close and not too far in distance. If the piston is too close, it is already substantially into the coil which creates the field and the instantaneous attractive force is reduced. Conversely, if the piston is too far away, the attractive force is reduced because the force is a function of the square of the distance. The piston is therefore attracted most successfully in an optimum range of positions which translate into optimum pulse width. The PWM assists in control of the heat dissipated by the coils. Inevitably, substantial current flow is involved and generates a notable heat output. While design factors can be modified to accommodate extraordinarily high temperatures, it is advantageous to avoid high temperatures by utilization of a reduced cycle. Heat that is created is proportionate to the current flow and the duty cycle of the current. While the current flow can be increased, a reduction in the duty cycle decreases the heat liberated. Accordingly, the present apparatus has one advantage: The creation of optimum torque in relation to the piston position while at the same time providing a more tolerable heat load on the apparatus. This is advantageous, particularly in light of the relatively high current levels which are required to generate a reasonable amount of torque in a converted magnetic engine.
As revealed in the parent disclosure, this apparatus is particularly adapted to be placed in a worn engine. The worn engine is salvaged by removing the pistons and the other apparatus associated with the carburation system. That material can be replaced by pistons formed of magnetic material (hereinafter referred to as plungers) and the substitution of coils in the cylinder holes. The present invention is able to convert a worn gasoline engine and extend the life of the engine block substantially. This is accomplished by placing inserts into the cylinders. A cylinder liner or sleeve is constructed and placed in the cylinder hole. It opens into the water jacket, and is supported from a replacement head. The head is markedly simplified in contrast with cylinder heads required for gasoline engines. Moreover, the cylinder head and sleeve support a coil form which is reduced in size so that water can flow around the coil, yet the coil form has sufficient size to encircle the plunger substituted for the removed engine piston.
An important advantage of the present invention is the use of two coils in each cylinder location. The two are wound on a common diameter about a spindle insert. One is located at the top end of the cylinder, and the other is located at the lower end of the cylinder when the insert is placed in the cylinder. This alters the torque that is sensed by the ferromagnetic piston as is reciprocates. The piston is attracted by magnetic forces. Attraction between two magnets, or a magnet and electromagnet, is determined by a square law relationship. This inverse square law relationship is a factor which limits coil construction. For instance, if a coil is particularly long and draws a relatively short piston into the volume of space of the coil, the attractive force drops markedly. The use of two coils which are separately energized gives marked advantage in the torque which is created. There is less stalling, stalling being the tendency of a piston to experience markedly reduced force acting on it after it enters near the centerpoint of the volume of space enclosed by the coil. Stalling is reduced through the time switching of the multiple coils chosen for this disclosure. While measurements are not readily obtained, it is submitted that this kind of positioning of smaller coils which are also relatively short in stature materially improves the torque obtained for a given rate of power consumption. The torque acting on the piston is increased by four-fold in theory.
Since more coils are used than is ordinarily the case, the pulse length can be modified. Pulse length modification is relatively easy for low current pulses. It's a far more difficult thing to accomplish with large current pulses, perhaps in the range of 50-100 amperes. This disclosure is directed to an equipment which provides pulses of the proper length to obtain torque for multiple coils acting on a single piston. The several coils are provided with timed or sequenced pulses which obtain high torque peaks (integrated by the flywheel) at a reasonable power consumption rate.
In light of the enhanced torque for a given current flow to the converted engine, and in further light of the modified head arrangement, the present disclosure has the advantage of a water cooled system for the coils. The coils are cooled to prevent continual resistance increase.
Pulse width modulation is thus incorporated in the present apparatus and has the advantage of cutting down on the time integral of the current flow in the coil and thereby reduces liberated heat.